The impact of quantum computing on the confidentiality of our data

Quantum computers will have many thousands times the computer power of today’s super computers. While there are many articles that identify the benefits of quantum computing, there are few tackling the implications on a key contributor to the confidentiality of our data today – encryption.

There are many methods today used to break encryption including brute force, precomputing and algebraic shortcuts. What is common is that their success is dependent on processing power.

There are tables abundant that relate a decryption time to a key length. While a little misleading, they do convey a principle in that there is a length of time that we can generally apply to the breaking of an encryption key of a certain length. Today, asynchronous encryption keys of 1024 bits are to be avoided, but not too long ago these were considered sufficient. With the advent of quantum computing, the time to decrypt key lengths that are today considered safe will considerably reduce.

What action will be needed?

Our response might be to up our game and use ever better encryption algorithms alongside increasing encryption key lengths. However, there are some areas where this is not a solution, and some forethought is required.

Data stores and backups are two key areas. Data that is encrypted in data stores and backups will have a life expiration of a value that is likely now to require consideration.

Simply put, data that was encrypted 4 to 5 years ago may need to be considered unencrypted, placing greater importance on the management of such data rather than a total reliance on its encryption. But more significantly will likely be the impact on confidentiality within the Internet and particularly cloud computing.

The utility of cloud computing is in its flexibility and the working freedoms it provides. This dynamism will not react well to increasing requirements for more complex and stronger encryption, with the storage of confidential data in the cloud becoming increasingly higher risk and secure cloud services becoming less flexible.

The role quantum computers can play

One group that will benefit from quantum computing is the owners of quantum computers! Encrypting techniques add random bits of data to our data and ‘re-encrypts’ the result through many hundreds of thousands of cycles, called interactions. To decrypt the data requires the reverse.

Using quantum computers, it becomes practical to put data through many times more iterations with the only realistic chance of reversing the process being to use a quantum computer.

We might think that we are safe for a while since very few will have such computers and if we keep our heads down, we should be ok. But for those with ‘state actors’ as threats in their threat profile, the availability of quantum computers will become a very real issue, and it requires planning today.